The P mint Trades from 1873-1876 are really hard to find in decent condition; the mintages were relatively low and many were sent overseas and melted. I found this one recently, in an older ANACS holder graded AU58. It has prooflike fields, and was probably dipped at some point. Moist of the hairlines are die polish lines, imo. Photographed to show the PL surfaces.
Funny, but most of those hairlines that you describe, I would think, appear (at least to me) to be on the holder......nice coin.
